The M27601 supports the prevailing AAL1 circuit emulation technology over its TDM links. It also supports AAL2 technology for more efficient bandwidth use along with real-time traffic processing. The combination of AAL1 and AAL2 in a single chip allows for the flexible provisioning of either or both services without the need for hardware upgrades. The M27601 also enables initial deployment of AAL1 hardware that can later be upgraded via firmware for AAL2 processing, either instead of or in addition to AAL1.